Nitish made an impressive 41 off 59 balls that lent a semblance of respectability to India's overall poor batting effort that yielded 150 in their first innings here at the Optus Stadium.
"I heard a lot about the Perth wicket. There was a bit of nervousness. It was in the back of my mind that everyone was talking about the bounce on Perth wicket. But then I remembered the chat I had with Gautam sir after our last practice session," Nitish told reporters during the post-day press meet.
"He was mentioning that 'when you get a bouncer, take it on your shoulder. It was like taking a bullet for your country'. That just boosted me. When he said that I felt that I needed to take the bullet for the country. That's the best thing I have heard from Gautam sir," he added.
The 21-year-old revealed that he was told about the impending debut a day ahead of the first Test, but gathered himself with a quiet dinner and an evening round of cycling.
"We got to know (him and pacer Harshit Rana) about our debut just one day ago, and we were excited. We were having dinner and we were keeping calm as last week.
"We did not want to take too much pressure. We had a cycle ride as well last evening, so that was good." he said.
Nitish was delightfully surprised when star batter and his idol, Virat Kohli, handed him the Test cap in the morning.
"It was a great feeling (getting a cap from Kohli). I have always dreamed about playing for India and it was a fantastic moment. Virat bhai is my idol when I started playing cricket. So getting a cap from him was a happy moment for me," he gushed.
Nitish was realistic about the beginning he made in Test cricket, and admitted that playing for India A at Melbourne recently helped him understand the Australian conditions.
"It was a good start, not a dream innings but a good start. To be honest, the India A series helped me a lot because it was my first time to Australia.
"Playing on this wicket compared to India, there are a lot of differences, the bounce etc. I felt there was more (help) off the wicket here (than at MCG), but apart from that the bounce and everything was the same as Melbourne," he detailed.
Perhaps, that experience reflected in his assault of Australian off-spinner Nathan Lyon, whom he carted for a few boundaries, including a reverse sweep.
"I thought the wicket was good for the fast bowlers and I had to make runs. When Nathan Lyon was bowling I saw two or three balls without any drift. So, I thought of taking on Lyon so that we get some quick runs," he said.
Nitish and Rishabh Pant added 48 runs for the seventh wicket to carry India from 73 for six to 121 before the latter got out for 37.
The Andhra cricketer said it was a good experience playing with Pant.
"It was good, you know, Rishabh is an aggressive batsman. He knows his game well and he was guiding me at that time as well. So, it was good playing with Rishabh," he added.
The Indian bowling unit under Jasprit Bumrah counterpunched to reduce the Aussies to 67 for seven at close, and Nitish said discipline was the watch word of the visiting bowlers.
"We were trying to hit the right areas. We were discussing disciplined bowling, so that's what I think Bumrah, Siraj and Harshit have done.
"Obviously, the wicket is helping a lot and we don't need to do a lot to get the wicket, just bowl in the right areas and let the ball do the rest," he said.
Nitish also lauded Bumrah's captaincy.
"He is very good...things like change of overs and spells were really good," he said.